Implement new BSMap.reset() method.
Simplify layer grab.
Refine darkness algorithm.

To be perfectly honest, I've no idea what the problem was anymore.
Implement keyboard control for player speed.

It gets a little frustrating waiting for the player to move about the
screen when you're debugging the program.
Bug fix in interface.

If the player were to try and move (i.e., press any the arrow keys)
while the game was in its title screen state, the game would become
unresponsive.
Bug fix.

If the player were to use a power, they would not be able to use any
other power for the rest of the game.  That's generally not a good
thing.